El escenario
A stereo preamp volume control uses an Arduino Nano to send I2C commands to a PT2258, with I2C pull-ups and power decoupling for clean control.
Qué hay en este dibujo
Lee las decisiones que hay detrás.
01
Use generic IC symbols for the Arduino Nano and PT2258 to keep the schematic renderable without pin-level library details
02
Add 4.7k pull-up resistors on SDA and SCL to 5V for reliable I2C signaling
03
Include 100nF and 10uF decoupling capacitors on the 5V rail and model audio in/out with AC sources and 10k loads
When documenting or teaching the wiring of an I2C-controlled volume IC with a microcontroller and stereo preamp signals.